Making a Difference
by Boreder
Summary: The traditional "Harry goes to 1977 to teach his parents DADA". Features a rather powerful Harry.
1. Prologue

Disclaimer: J. owns Harry Potter and the Potterverse. The plot, however unoriginal, is mine.

_1977...._

Albus Dumbledore had a problem.

He had this particular problem every year. His latest Defence Against the Dark Arts teacher had resigned. Now he needed a new one, again...

This year, no-one seemed to want the position. He had put an notice in the Daily Prophet, but still no luck. The rumors about the position being cursed had spread too far.

He would have to ask the Ministry for help if someone didn't come soon.

Albus was musing in his office when suddenly the door opened and a young man, seemingly a seventh year student, entered. But, as Albus realized, this was no seventh year, as he had not seen the man before. He had messy, shoulder length brown hair, startlingly green eyes and a very powerful aura around him. Albus could feel the magic in the air, coming from this young man.

"Good evening. Can I help you, Mr...?" Albus asked, a little wary of this stranger. The times were rough, with the war going on and Death Eaters constantly coming up with new methods to wreak havoc among the people. Strangers weren't very well received anywhere.

"Good evening, sir. My name is Harrison Peters. I'm here to apply for the Defence Agaisnt the Dark Arts position. I believe the post hasn't been taken yet?"

"Indeed, it is still open. Please sit down, Mr. Peters."

Albus scrutinized the young man intently. Peters didn't even flinch under his gaze, which was unusual.

"May I enquire your age, Mr. Peters? You seem rather young to be a teacher." The statement held no malice, it was merely curious.

"I turned nineteen last July. And yes, I know I'm young, but I have plenty of experience."

Albus looked directly into his eyes, and was shocked. Those green eyes held great amounts of sorrow, wisdom and most of all, experience.

"Hmm.. May I see your qualifications?" Albus was getting interested.

Peters reached into his pocket, pulled out a few parchments and handed them to the headmaster, who examined them closely.

"Six N.E.... O's in DADA, Tranfiguration, Charms and Potions, E's in Herbology and Arithmancy...this is quite excellent!"

"Thank you sir. I've only studied Arithmancy for a few years, but I seem to be a natural. DADA is still my favorite subject, though."

"Very well. Now I shall test your skills. First, take this test. After that, I want to see some of your skills in practise. I'll let you beging the test now."

Peters grabbed a quill and started answering questions on the parchment. He was done in twenty minutes. Albus eyed the paper, and was shocked again.

"Full marks! That must've been the fastest time yet, too. If you can pass these practical tests, the post is definitely yours. Peters smiled widely.

He started casting the spells Albus asked him to. He managed them all, and as a bonus cast the Expecto Patronum too. Albus was speechless.

"You are more than qualified for the job. There is still a little problem, though. During these dark times, I must have utmost trust in my staff."

"Could you show me your left arm?" Albus asked, a little bit of him still expecting to see the infamous Mark. Peters removed these fears, as his arm was clean of any marks.

"Excellent. Welcome to Hogwarts, professor Peters! I'll get professor McGonagall to show you your classroom and living quarters. The term will start in a few days, on 1st of September. Your predecessor left a curriculum, but you are free to modify it. Please inform me of any drastic changes to it, however. Ah, there you are Minerva. Could you show our new DADA teacher to his work area and quarters?

McGonagall, who had just entered, nodded to Albus and asked Peters to follow him.

"Thank you headmaster, and good night."

"Good night."

Peters left with McGonagall. As the door closed behind them, Albus was left to his thoughts. This newcomer was a very powerful wizard, even more powerful than himself. Possibly even more powerful than Voldemort. Voldemort! Albus had to make sure Peters wouldn't join the Death Eaters. With that level of power, the Light side would be doomed.

Fortunately, Peters was staying in Hogwarts for now. Perhaps he could join the Order later...

Maybe there was hope for the war after all.

Meanwhile, a very happy but very tired Harrison Peters was looking around his new living quarters. In truth, they were already familiar to him, having been there numerous time in the past. Or rather, the future. The future which he was about to change.


	2. Chapter 1

Disclaimer: J. owns Harry Potter and the Potterverse. The plot, however unoriginal, is mine.

_Chapter One_

When Harry woke up the following day, he didn't remember anything for a moment. He wondered where he was and why he was sleeping with all his clothes on.

Then it all came back.

He had done it. He had traveled back in time! Well, that wasn't really a feat in itself, he had traveled in time before. Except this time, he had done the impossible and went back by over twenty years! And now... he was about to change the past.

No one knows what happens if you try to disturb the timeline. No one even knows if you _can_ disturb the timeline. Harry had thought long about this. If you can't change the timeline, that would mean he was supposed to come back in time. Maybe he did it in the original timeline and something happened to him? Maybe he came and died in 1977 and couldn't change a thing. That was a very real possiblity.

He had to test this theory. What could he change irreparably? He could tell about all this to Dumbledore. But what if the old man obliviated him, trying to conserve the timeline. No, he wouldn't tell Dumbledore anything. Something else...

The horcruxes! Voldemort had probably made all of them, except the accidental one that would come in a few years. NO! It wouldn't come, at all, if Harry had a say in it. The burning question was, did he?

Harry thought furiously. The diary, the ring, the locket, the cup, the diadem and the snake. No, wasn't the snake made into a horcrux later? That means he has five horcruxes now...

The diary is out of reach at the moment. Harry didn't know if Malfoy had it at this point. _He can't have it, he's barely left school! I doubt he's even in Voldemorts inner circle yet. _The ring is in the ruins of the Gaunt's house. Harry knew how to get it, but it wouldn't be easy. The locket hadn't been stolen by Regulus yet, which made another hard to reach horcrux. The cup might be in Gringotts or still in Voldemorts possession. That left the diadem, which was incidentally the easiest to find.

Harry got up from the bed and half walked, half ran from the room, stopping only to grab the Invisibility cloak and the Marauders map from his trunk.

Several minutes later, Harry was walking back and forth in front of a wall on the seventh floor. A door appeared suddenly, and Harry entered quickly. The room was huge, and full of different things, just as Harry remembered. He walked past the numerous shelves, searching, until his eyes came upon a familiar diadem.

Carefully, Harry took the diadem and examined it. It was definitely a horcrux: the evil aura around it was enough proof. Now he just had to destroy it and prove he COULD change the past.

Harry quickly trekked back to his quarters with the diadem and searched his trunk. Soon he found it: a souvenir basilisk fang from the Chamber. Taking a deep breath, he aimed and stabbed the diadem.

Black substance leaked from it profusely. Harry thought he heard a distant scream of pain. And then, it was over. The horcrux was no more.

Shakily, Harry put the now ruined diadem and the (sheltered) fang back into his trunk, along with the Cloak. He was about to put the Marauder's map back too, when he realized something. Looking into the map, he saw the tiny dot "Harry Potter".

He had almost forgotten this particular problem. Luckily, there was an relatively easy solution. After casting a special Confundus Charm on the parchment, it read "Harrison Peters".

Unfortunately, the Marauders had their own map (_well, this is their map too_, thought Harry). He had to enchant it too, without the Marauders knowing. Preferably as soon as possible...

Frowning in thought, Harry started unpacking his belongings.

Unknowingly, Harry had already saved two innocent lives in his quest for a better future. Because the DADA teacher position was taken by Harry, Dumbledore wasn't forced to ask the Ministry for help this time. Therefore Stephen Cooper, a veteran auror, wasn't needed for the job. Two weeks later his home was attacked by several Death Eaters. In the original timeline, Stephen was teaching at Hogwarts while his wife and son were killed in the attack.

THIS time however, Stephens managed to defend his home long enough for them all to escape with non-fatal injuries, killing one Death Eater and injuring a few in the process.

The killed Death Eater was named Walden Macnair.


	3. Chapter 2

Disclaimer: J. owns Harry Potter and the Potterverse. The plot, however unoriginal, is mine.

* * *

_Chapter Two_

After doing some paperwork with Dumbledore and discussing "Harrison's" salary, Harry had one free day before the term began. He was getting nervous sitting around in his office, so he decided to go shopping for the day.

Harry apparated to Diagon Alley and found it to be extremely busy. He soon remembered that it was the last day for Hogwarts students to buy their school supplies. He had been hoping for a quiet, relaxing trip to get his mind off work, but this really had the opposite effect. Cursing his dodgy memory and stupidity, he plodded to Gringotts.

Thinking back to the time when he broke in to steal Hufflepuff's Cup, Harry was very glad to be in past where the goblins weren't hostile to him. Harry had visited Gringotts once in the future after his break-in. The goblins were furious. After hours of negotiations, Harry was able to leave with all of his money, thought he had to pay large amounts of gold to repay for the damages. The goblins had made clear that he wasn't welcome there anymore. Harry didn't really mind, as he was already planning his time-travel trip at the time.

Shaking his head at the memories, Harry approached a lone goblin who looked up from a stack of parchment and asked him: "How can I help you, mister...?"

"Po- Peters. My name is Harrison Peters, and I'd like to open a new vault." Harry berated himself silently for almost slipping his name already. The goblin didn't seem to notice anything.

"Well, mister Peters, we have several types of vaults here in Gringotts. They range from Class A to E, with Class A vaults being the smallest and cheapest, to Class E having the largest, most secure and expensive vaults. There are also separate vaults for items such as family heirlooms."

During the goblins speech Harry had laid his trunk on the floor, enlargened it and used his key on the sixth lock (out of nine). The trunk opened and inside it were stairs downwards. Harry motioned to the goblin to follow him and climbed into the trunk. At the end of the stairs there was a door. Harry opened it and walked in, the goblin coming behind him.

They had walked into a huge room, probably even bigger than the Great Hall at Hogwarts. Apart from the small clearing near the doorway, the hall was full of gold. Impossibly large piles of Galleons were everywhere. Harry smirked at the goblins expression: it was pure shock. After a minute of silence, Harry cleared his throat and the goblin snapped out of his stupor. In a weak voice, he inquired: "Class E, I take it?"

It took over a hour for the goblins to transfer the money to the new vault and do the necessary paperwork. Harry was introduced to Ragnok, the current leader of Gringotts. Apparently, Harry was now the richest person in London. With the combined heritages from both Potter and Black family vaults, this was no surprise to Harry. He appointed some goblins to take care of his finances and investing. At the end Harry shaked hands with Ragnok, which shocked Harry a bit, as the goblins very rarely did anything like that with wizards.

Leaving Gringotts behind, Harry first went to Flourish and Blotts and bought several interesting books, most of them about Defence or Arithmancy.

He was just about to leave the shop, when he saw some familiar people entering. Harry freezed on the spot.

17-year old James Potter, Sirius Black and Peter Pettigrew walked in. James and Sirius were talking about Quidditch, while Peter just tailed them silently.

Harry had been training for this moment, but he still couldn't keep a neutral face. He had to use occlumency to keep out his overwhelming emotions. His first reaction would've been to go and strangle Pettigrew immediately, but he had to remind himself that he wasn't a traitor yet. At least he didn't have the Dark Mark yet. Maybe Harry could prevent that too.

James really looked like him at that age. The only differences were his brown eyes, really. Even now they'd be like carbon copies if Harry hadn't changed his hair.

Harry took notice of James's demeanor: he wasn't nearly as cheery as Sirius, and a lot of his smiles seemed a bit forced. There was sadness in his eyes, Harry thought. Maybe it was the year when his parents (and Harry's grandparents) died.

Sirius was unlike Harry had ever seen him. Energetic like no other, he practically flew around the shop, looking for the correct books. He clearly tried to improve James's mood, cracking jokes and goofing around.

Peter was mostly quiet, occasionally taking part in the discussions. The young Peter didn't really look at all like his future counterpart. Even now, it was hard for Harry to understand how he could become on of Voldemort's Death Eaters.

Harry watched silently as the Marauders looked for their school books. It took him a moment to notice that Remus was missing: maybe it was too close to full moon for him to come. That reminded Harry of another thing, and he swiftly left the shop and headed to the Apothecary.

* * *

The sun was setting when Harry finally finished his shopping. Now he was materially prepared for the coming year. Mentally, he was preparing for the eventual meeting of his seventh-year class...


End file.
